1. Department of Otolaryngology–Head and Neck SurgeryTohoku University Graduate School of Medicine Sendai Japan
2. Sen‐En Rifu Otological Surgery Center Miyagi Japan
3. Department of Otolaryngology–Head and Neck SurgeryNihon University School of Medicine Tokyo Japan
4. Department of Otolaryngology–Head and Neck SurgeryHamamatsu Medical Center Hamamatsu Japan
5. Department of Otolaryngology–Head and Neck SurgeryHamamatsu University School of Medicine Hamamatsu Japan
6. Clinical Research, Innovation and Education CenterTohoku University Hospital Sendai Japan
7. Division of BiostatisticsTohoku University Graduate School of Medicine Sendai Japan